JPH0547906A - Plane object holding means and equipment using the same - Google Patents

Abstract

PURPOSE:To provide a plane object holding means which holds a plane object like a semiconductor wafer in a clean state of high purity and is capable of attitude control of high precision, and an equipment which uses the means. CONSTITUTION:The subject equipment is a photoresist baking process equipment which is used in the photoetching process of a semiconductor wafer 1, which is arranged on a heater-buried type heater block 3 via a pin plate 2 made of single crystal sapphire. The upper surface of the semiconductor wafer 1 is coated with a photoresist film 4 which patterns a semiconductor element circuit on the wafer 1 surface. A wafer retaining protrusion 5 for holding the semiconductor wafer 1 is formed to have a square shape of 0.1X0.1mm and a height of 0.1mm. Its contact surface is so precisely worked that the Ra value of surface roughness is smaller than or equal to 0.1mum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for handling and holding a plate-like material, and more particularly to a semiconductor wafer, a liquid crystal, etc. in a semiconductor manufacturing industry, a liquid crystal substrate manufacturing industry, a magnetic disk manufacturing industry, a multilayer wiring board manufacturing industry and the like. When handling and holding plate-like objects such as substrates, magnetic disks, and multilayer wiring boards, etc., plate-like objects such as semiconductor wafers that can be handled or held in a clean and highly pure state and whose posture can be controlled accurately. The present invention relates to a holding means and a technique effectively applied to a device using the holding means.

[0002]

2. Description of the Related Art Conventionally, in the semiconductor manufacturing industry, liquid crystal substrate manufacturing industry, magnetic disk manufacturing industry, and multilayer wiring board manufacturing industry, various plate-like materials such as semiconductor wafers, liquid crystal substrates, magnetic disks, and multilayer wiring boards are manufactured. Handling or holding,
Attitude control technology is widely used.

In the semiconductor manufacturing industry, the degree of integration of semiconductor products is increasing year by year, and a 16 Mbit DRAM (Dynamic Random Access Memor) with a design rule of 0.5 μm process.
y) LSI is being developed. This 0.5 μm process L
In order to manufacture SI products with high quality, it is necessary to control the adhered foreign matters to the wafer of 0.05 μm size, which corresponds to 1/10 of the minimum pattern size.

For example, regarding the photoresist processing step for patterning semiconductor elements on a semiconductor wafer, the problem of foreign matter adhering to the front surface of the wafer and the problem of foreign matter adhering to the back surface of the wafer are important issues.

The former problem of foreign matter adhering to the wafer surface is
The problem is that foreign matter attached to the surface of the wafer directly leads to poor appearance of the semiconductor element pattern (wiring short circuit, disconnection failure).

On the other hand, with regard to the latter foreign matter adhered to the back surface of the wafer, the following problems have been clarified.

(1). In a reduction projection exposure apparatus that optically transfers a semiconductor element pattern onto a photoresist film coated on a semiconductor wafer, if a semiconductor wafer is vacuum-adsorbed on a wafer holder of an exposure stage with foreign matter attached to the back surface of the wafer. The wafer is locally deformed at the foreign matter portion adhering to the back surface of the wafer, and during the exposure processing, the deformed portion of the wafer causes a focus image plane shift, resulting in poor resolution.

(2) In a batch type wet processing apparatus such as a photoresist removing processing apparatus and various cleaning processing apparatuses, foreign matter adhering to the back surface of the wafer is transferred and adhered to the wafer surface through the processing liquid, resulting in poor appearance of the semiconductor element pattern. And metal contamination problems arise.

As a publicly known example of the measure for reducing the foreign matter adhering to the back surface of the wafer, as shown in Japanese Patent Laid-Open No. 63-107117, a separable plate is attached to the heater body of the baking device, and the plate is attached. There is a technique to remove and wash periodically. As a result, the semiconductor wafer can be vacuum-sucked and baked on the plate that is always kept clean.

Further, regarding the reduction projection exposure apparatus, Japanese Patent Publication No. 60-155147 and JP-A-1-129.
As disclosed in Japanese Patent No. 438, 438, as a vacuum suction structure of an exposure stage wafer holder, a vacuum-sucked semiconductor wafer is suction-fixed with a flatness of ± 0.5 μm or less, and the flatness of the flatness due to inclusion of foreign matter on the back surface of the wafer A vacuum suction fixing base intended to prevent the deterioration is disclosed.

[0011]

However, the above-mentioned conventional techniques cannot be said to be sufficient as a measure for reducing the adhered foreign matter on the semiconductor wafer, and therefore, the present inventor has proposed that the photoresist treatment in the semiconductor manufacturing industry should be performed. With respect to the photoresist processing apparatus used in the process, for the purpose of clarifying the cause of the adhering foreign matter on the back surface of the semiconductor wafer, the factor of adhering foreign matter on the back surface of the semiconductor wafer was analyzed.

As a result, it was revealed that the number of foreign matters adhering to the back surface of the wafer was large in descending order of contact area with the semiconductor wafer. For example, regarding a photoresist processing apparatus, the number of foreign matters adhering to the back surface of the wafer transferred from the heater surface of each bake processing section (about 80%) and the number of foreign matters adhering to the back surface of the wafer transferred from the spin chuck surface of the coating processing section ( 15%), and the number of adhered foreign matters (about 5%) on the back surface of the wafer transferred and adhered from the wafer support pin surface of the wafer transfer unit increases in this order. Furthermore, it was revealed that the map of the adhered foreign matter on the back surface of the wafer by the defect inspection apparatus for the semiconductor wafer surface and the shape of the semiconductor wafer supporting portion are the same.

This evaluated photoresist processing apparatus is a system in which a removable quartz plate is provided on the heater surface of each of the various baking processing sections, and a semiconductor wafer is adsorbed and heated on the quartz plate. In addition, the semiconductor wafer adsorption spin chuck in the coating section is a removable high-purity Poly-ether Ether Ketone.
In addition, the semiconductor wafer transfer section is made of removable quartz pins.

In this case, the quartz plate of the bake processing section, the spin chuck of the coating section, and the quartz pin of the semiconductor wafer transfer section are regularly removed and cleaned. In this way, the holding members for various semiconductor wafers are regularly cleaned, but the chemicals used for cleaning are limited due to the restriction of using materials such as quartz materials and polyether / etherketone materials, and plasma cleaning. However, depending on the type of foreign matter, there is a problem that it cannot be completely removed and a clean state cannot be obtained.

As a result, as described above, foreign matter is transferred and adhered from the wafer holding member to the back surface of the semiconductor wafer in proportion to the contact area with the semiconductor wafer during the wafer handling process.

It is clear that the foreign matter brought in by the semiconductor wafer itself being processed adheres to the holding member of the semiconductor wafer and is transferred and adhered to the back surface contact portion of the semiconductor wafer to be handled next. It was

Further, the inventor of the reduction projection exposure apparatus analyzed the degree of occurrence of defective resolution due to foreign matter adhering to the back surface of the wafer.

For example, the known Japanese Patent Laid-Open No. 1-129438.
In the vacuum suction structure of the exposure stage wafer holder disclosed in Japanese Patent Publication, although the flatness of the semiconductor wafer can be prevented from lowering during vacuum suction due to the presence of foreign matter adhering to the back surface of the wafer in the short term, The contact surface pressure between the semiconductor wafer and the vacuum suction portion during suction of the semiconductor wafer increases due to the reduction of the contact area with the vacuum suction portion. Therefore, when used for a long time, the vacuum suction portion of the wafer holder is partially worn, and the flatness of the semiconductor wafer during vacuum suction is reduced.
As a result, it has been clarified that a focus image plane shift occurs during the exposure process, resulting in poor resolution.

Further, as a new problem, when the holding member of the semiconductor wafer is made of an insulating material such as quartz material or polyether / etherketone material, static electricity is generated and accumulated in the wafer holding member during handling of the semiconductor wafer. It was revealed that the accumulated static electricity adsorbs and accumulates microscopic dust on the wafer holding member.

Therefore, an object of the present invention is as a holding member for holding a plate-like material, single crystal sapphire excellent in mechanical strength, chemically extremely stable, and excellent in acid resistance, alkali resistance and plasma resistance. It is an object of the present invention to provide a plate-like object holding means capable of handling and holding a plate-like object in a clean and highly pure state by using a material, and an apparatus using the same.

Further, another object of the present invention is to provide a plate-like object holding means capable of preventing the generation of static electricity by forming an electrically conductive film on the surface of a holding member, and an apparatus using the same. It is in.

Still another object of the present invention is a plate-like object holding means capable of reducing the contact area between the plate-like object and the holding member and reducing foreign matter transferred from the holding member to the plate-like object. It is to provide a device using the.

Still another object of the present invention is to provide a plate-like object holding means capable of processing the flatness of the plate-like object adsorption surface with high accuracy and controlling the posture with high accuracy, and a device using the same. To do.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0025]

Among the inventions disclosed in the present application, a brief description will be given to the outline of typical ones.
It is as follows.

That is, the plate-shaped object holding means of the present invention holds the plate-shaped object through the holding member made of a single crystal sapphire material.

Further, another plate-shaped material holding means of the present invention holds the plate-shaped material through a holding member which is made of a single crystal sapphire material and has an epitaxial silicon film grown thereon.

In this case, the shape of the contact surface of the holding member with the plate-like object is a point contact surface shape, a line contact surface shape, or a combination thereof.

The contact surface of the holding member is 0.5 μm.
The flatness and the surface roughness of Ra value of 0.1 μm or less are processed as follows.

Further, the apparatus of the present invention uses the plate-shaped object holding means to handle or process the plate-shaped object.

[0031]

According to the plate-like object holding means described above, the holding member is made of the single crystal sapphire material, so that the plate-like object is handled in a clean and high-purity state, and the posture is accurately controlled and held. be able to.

That is, single crystal sapphire is excellent in mechanical strength, is about 7 times as hard as a semiconductor silicon wafer, and is excellent in abrasion resistance. For example, the following is a comparison between quartz and alumina ceramics, which are mainly used as a semiconductor wafer handling member and a wafer holding member of a semiconductor wafer manufacturing apparatus, and single crystal sapphire used in the present invention.

[0033]

[Table 1]

In particular, since single crystal sapphire is hard and has a high bending strength, it can be processed into a shape on the order of μm by precision grinding, precision polishing, and precision lapping, and a flatness of 0.5 μm or less can be obtained. In addition, the surface roughness of the machined surface can be 0.1 μm or less in Ra value. As a result, the surface roughness of the contact surface between the plate-like object and the holding member can be processed to 0.1 μm or less, and the unevenness of the contact surface can be reduced to prevent the accumulation of foreign matter on the uneven portion. It is possible to reduce foreign matter that is transferred and attached from the holding member to the plate-like object when handling or holding the plate-like object.

Further, in this case, the contact surface shape of the holding member is a point contact surface shape, a line contact surface shape, or a combination thereof, so that the contact area with the plate-like object can be reduced. As a result, the number of foreign matters attached to the holding member by transfer onto the plate-like object can be reduced.

On the other hand, single crystal sapphire is a single crystal containing Al ₂ O ₃ as a main component, is chemically extremely stable, and has excellent acid resistance, alkali resistance and plasma resistance. As a result, the holding member can be cleaned by various methods such as a cleaning treatment with an acidic chemical solution, an alkaline chemical solution, or a plasma treatment. Is possible.
In particular, since the surface roughness of the contact surface is formed to be 0.1 μm or less as described above, a synergistic effect in which the unevenness of the contact surface is small and foreign matter attached to the contact surface is easily removed can be expected.

Further, according to the other plate-shaped object holding means described above, the growth of the epitaxial silicon film on the holding member can prevent static electricity from being generated in the holding member. Accordingly, when handling or holding the plate-like object, it is possible to prevent microscopic dust due to static electricity generated in the holding member from adhering to the contact surface of the holding member, and prevent accumulation of foreign matter due to the dust adhesion.

Further, according to the apparatus using the plate-shaped object holding means described above, the flatness of the plate-shaped object can be controlled to be 0.5 μm or less, so that the processing failure caused by the flatness can be prevented. can do.

Further, since it is possible to reduce the number of foreign matters adhering to the holding member and the number of foreign matters adhering to the plate member transferred from the holding member, it is possible to perform a clean process which is not affected by the foreign matters.

[0040]

[Embodiment 1] FIG. 1 is a schematic cross-sectional view showing a principal part of a photoresist baking processing apparatus which is an embodiment of a plate-like object holding means and an apparatus using the same according to the present invention.

First, the construction of the essential parts of the photoresist baking processing apparatus of this embodiment will be described with reference to FIG.

The photoresist baking processing apparatus of this embodiment is used, for example, in a photoetching process in a semiconductor wafer manufacturing apparatus, and the semiconductor wafer (plate-like object) 1 is
It is installed in the heater embedded heater block 3 via a pin plate (holding member) 2 made of single crystal sapphire made of a single crystal sapphire material excellent in mechanical processing accuracy and chemical characteristics. Then, on the semiconductor wafer 1, a photoresist film 4 for patterning a semiconductor element circuit pattern on the surface of the semiconductor wafer 1 is applied.

On the other hand, a single crystal sapphire pin plate 2
Is provided with a wafer supporting protrusion 5 that supports the semiconductor wafer 1. Although not shown, the wafer supporting protrusions 5 are provided at three locations on a concentric circle at equal intervals. The wafer supporting protrusion 5 has a contact surface shape for supporting the semiconductor wafer 1 of, for example, 0.1 mm × 0.1 mm.
It has a square shape and has a height of 0.1 mm.

The aim of this dimension is to reduce the contact area between the single crystal sapphire pin plate 2 and the semiconductor wafer 1 into a square shape of 0.1 mm × 0.1 mm, from the heater block 3 to the single crystal sapphire pin plate. In order to increase the efficiency of heat transfer to the semiconductor wafer 1 via the wafer 2, the height of the wafer supporting protrusions 5 is set to 0.1 mm.

Further, in order to reduce the unevenness of the contact surface between the semiconductor wafer 1 and the wafer supporting protrusion 5, the surface roughness of the contact surface of the wafer supporting protrusion 5 is precisely processed to an Ra value of 0.1 μm or less. There is.

The heater block 3 is provided with a vacuum suction hole 6 for vacuum-sucking the single crystal sapphire pin plate 2. The method of vacuum-adsorbing the single crystal sapphire pin plate 2 is intended to facilitate the attachment and detachment of the single crystal sapphire pin plate 2 and to improve the cleanability of the single crystal sapphire pin plate 2. ..

Next, with respect to the operation of this embodiment, a method of baking the photoresist film 4 on the semiconductor wafer 1 will be described.

First, the single-crystal sapphire pin plate 2 is evacuated by the vacuum suction holes 6 on the heater block 3 and vacuum-sucked. In this state, the photoresist film 4 coated on the semiconductor wafer 1 is heated to a predetermined temperature for baking treatment, for example, 90 ° C.

When the temperature of the heater block 3 reaches a predetermined baking temperature, the semiconductor wafer 1 coated with the photoresist film 4 is handled by a wafer handler (not shown) and the pin plate 2 made of single crystal sapphire 2 is handled. Set on top. In this state, when the processing is performed for a predetermined time, for example, 240 seconds, the baking of the photoresist film 4 is completed, and the wafer handler handles it by another processing module.

Therefore, according to the photoresist baking processing apparatus of this embodiment, since the holding member of the semiconductor wafer 1 is made of the single crystal sapphire material, the semiconductor wafer can be processed by the mechanical processing accuracy and the chemical characteristics of the single crystal sapphire. 1 can be maintained in a clean and highly pure state.

Further, since the contact surface shape of the wafer supporting projection 5 is a square shape of 0.1 mm × 0.1 mm, the contact area with the semiconductor wafer 1 is reduced and the single crystal sapphire pin plate 2 is used. It is possible to reduce foreign matters transferred from the semiconductor wafer 1 to the semiconductor wafer 1.

In particular, since the surface roughness of the contact surface is precisely processed to 0.1 μm or less, the unevenness of the contact surface can be reduced to prevent the accumulation of foreign matter and further reduce the foreign matter to be transferred and adhered. ..

Further, in addition to reducing the contact area of the wafer supporting protrusion 5, the height of the wafer supporting protrusion 5 is set to 0.1 mm so that the heat transfer efficiency from the heater block 3 to the semiconductor wafer 1 can be improved. Therefore, the heating efficiency of the baking process is good, and the reduction of the contact area enables a clean heating process with a small number of transferred foreign matters.

[0054]

[Embodiment 2] FIG. 2 is a schematic sectional view showing a single crystal sapphire wafer holder of a reduction projection exposure apparatus which is another embodiment of the plate-like object holding means and the apparatus using the same according to the present invention.
4A and 4B are a plan view and a front view showing the wafer holder in this embodiment.

The reduction projection exposure apparatus of the present embodiment is used for the exposure processing after baking of the first embodiment, for example, in the photoetching process in a semiconductor wafer manufacturing apparatus.
A semiconductor wafer (plate-like object) 1a coated with an unexposed photoresist film 4a is vacuum-adsorbed on a single crystal sapphire wafer holder (holding member) 7 made of a single crystal sapphire material. Then, the single crystal sapphire wafer holder 7 is fixed on the exposure stage 8 with one touch, and the exposure stage 8 is three-dimensionally controlled in position and orientation by the exposure stage drive unit 9.

On the other hand, above the exposure stage 8, the UV light 10 is irradiated from a UV light source (not shown). The UV light 10 passes through the reticle 12 set on the reticle support 11, and further reduces the semiconductor element circuit pattern drawn on the reticle 12 by the reduction projection lens 13 to obtain the single crystal sapphire wafer holder 7
An image is formed on the photoresist film 4a on the semiconductor wafer 1a adsorbed on the substrate, and the photoresist film 4a is exposed.

The exposure stage 8 has a built-in wafer transfer pin driving section 14 for the vertically moving semiconductor wafer 1a, and the semiconductor transfer pin 15 is used to transfer the semiconductor wafer 1a.

Further, regarding the single crystal sapphire wafer holder 7, the single crystal sapphire wafer holder 7 described with reference to FIGS. 3 and 4 is provided with a wafer vacuum suction port 16 for vacuum suction of the semiconductor wafer 1a. Further, for the purpose of adsorbing the semiconductor wafer 1a with a predetermined vacuum force, an outer peripheral ring 17 having a width of 0.1 mm is provided to bring the outer peripheral back surface of the semiconductor wafer 1a into contact with each other to prevent vacuum leak.

On the other hand, a wafer delivery pin escape hole 18 which is an escape hole for the wafer delivery pin 15 of the wafer delivery pin driving section 14 for delivering the semiconductor wafer 1a is provided. A wafer transfer pin escape hole ring 19 having a width of 0.1 mm is provided on the outer periphery of the wafer transfer pin escape hole 18 for the purpose of preventing a vacuum leak when the semiconductor wafer 1a is vacuum-sucked.
Is provided.

Further, the single crystal sapphire wafer holder 7 has an outer peripheral ring 17 and a wafer delivery pin escape hole for the purpose of controlling the flatness of the semiconductor wafer 1a to 0.5 μm or less when the semiconductor wafer 1a is vacuum-sucked. Ring 1
A plurality of wafer supporting protrusions 20 each having a square contact surface of 0.1 mm × 0.1 mm are arranged in the space between the plurality of wafers 9.

As described above, the outer peripheral ring 17,
The wafer suction surface 21 shown in FIG. 4, which is composed of the wafer delivery pin clearance hole ring 19 and the wafer supporting protrusion 20, is precisely processed to have a flatness of 0.5 μm or less, and the surface roughness of the contact surface is Ra value 0. Precisely processed to less than 0.1 μm.

Next, with respect to the operation of this embodiment, a method for exposing the semiconductor element circuit pattern drawn on the reticle 12 to the photoresist film 4a on the semiconductor wafer 1a will be described.

First, when an unexposed semiconductor wafer 1a is handled on the exposure stage 8 by a wafer handler (not shown), the wafer transfer pin driving unit 14 of the semiconductor wafer 1a is raised to move the semiconductor wafer 1a to the wafer transfer pin. Received by 15.

Then, the wafer delivery pin 15 is lowered,
It is transferred onto the single crystal sapphire wafer holder 7. Then, the wafer vacuum suction port 16 of the single crystal sapphire wafer holder 7 is evacuated to vacuum suction the semiconductor wafer 1a with a predetermined suction force.

Further, the semiconductor wafer 1a is completely brought into close contact with the wafer suction surface 21 of the single crystal sapphire wafer holder 7, and the posture is controlled by following the flatness of the wafer suction surface 21. In this state, the exposure stage drive unit 9 drives the exposure stage 8
3D position control and irradiate UV light 10
The reticle 1 is attached to the photoresist film 4a on the semiconductor wafer 1a which is vacuum-adsorbed by the single crystal sapphire wafer holder 7.
2 expose the semiconductor device circuit pattern depicted above.

Therefore, according to the reduction projection exposure apparatus of the present embodiment, the holding member for the semiconductor wafer 1a is made of a single crystal sapphire material, and the wafer supporting protrusion 20 is 0.1 mm.
× 0.1mm square contact surface, this contact surface roughness is 0.1μm
By performing the precision processing below, the semiconductor wafer 1 can be maintained in a clean and highly purified state as in the first embodiment, and it becomes possible to reduce foreign substances transferred to the semiconductor wafer 1.

Furthermore, since a plurality of wafer supporting protrusions 20 are arranged and the wafer suction surface 21 is precisely processed to a flatness of 0.5 μm or less, the flatness of the semiconductor wafer 1a is 0.5 μm.
The posture is controlled as described below, and it is possible to prevent the occurrence of the resolution defect of the pattern transfer due to the poor flatness.

[0068]

[Embodiment 3] FIG. 5 is a schematic cross-sectional view showing an essential part of a single crystal sapphire spin chuck of a photoresist coating processing apparatus which is still another embodiment of the plate-shaped article holding means and apparatus using the same according to the present invention. is there.

The photoresist coating apparatus of this embodiment is
For example, in a photo-etching process in a semiconductor wafer manufacturing apparatus, the semiconductor wafer (plate-like material) 1 used for the baking and the coating treatment before exposure in Examples 1 and 2
The photoresist liquid 23 is dropped onto the surface b from the dropping nozzle 22 and spin-coated. Then, the semiconductor wafer 1b is vacuum-sucked on a single-crystal sapphire spin chuck (holding member) 24 made of a single-crystal sapphire material.

The wafer suction surface 25 that vacuum-sucks the semiconductor wafer 1b is 0.1 in the same manner as the wafer suction surface 21 of the single crystal sapphire wafer holder 7 shown in FIG.
An outer peripheral ring with a width of mm and a plurality of wafer supporting protrusions each having a contact surface shape of a square of 0.1 mm × 0.1 mm are arranged.
It is formed into a semiconductor wafer suction surface shape precisely processed to have a flatness of less than μm and a surface roughness of Ra value of less than 0.1 μm.

Further, on the surface layer portion of the single crystal sapphire spin chuck 24, an electrically conductive silicon film 26 is epitaxially grown for the purpose of preventing static electricity generation.

Next, the processing method of this embodiment will be described. The semiconductor wafer 1b is vacuum-sucked to the spin chuck 24 made of single crystal sapphire, and the predetermined rotation speed, for example, 10
While rotating at a rotation speed of 00 rpm, the dripping nozzle 22
A predetermined amount of photoresist solution 23 is dropped from the above to form a photoresist film 4b on the semiconductor wafer 1b.

Therefore, according to the photoresist coating apparatus of the present embodiment, the holding member for the semiconductor wafer 1b is made of a single crystal sapphire material, has a square shape of 0.1 mm × 0.1 mm, and has a surface roughness of 0. By precisely processing the contact surface to less than .1 μm, it is possible to keep the semiconductor wafer 1b in a clean and high-purity state as in Examples 1 and 2, and reduce the number of foreign particles transferred to the semiconductor wafer 1b. Moreover, the semiconductor wafer 1b can be subjected to the coating process by controlling the posture of the flatness of 0.5 μm or less.

Although the invention made by the present inventor has been specifically described based on the first to third embodiments, the present invention is not limited to the above-mentioned embodiments, and various modifications are possible without departing from the scope of the invention. Needless to say, it can be changed.

For example, in each of the above-described embodiments, the photoresist processing apparatus and the reduction projection exposure apparatus in the semiconductor wafer manufacturing apparatus have been described, but the present invention is not limited to the above-mentioned embodiments, and the dry processing for processing in a vacuum is performed. Etching processing equipment, plasma CVD processing equipment, photo CVD
It can be widely applied as a semiconductor wafer handling and holding means in various processes such as a processing device and an ion implantation processing device.

Further, the holding means is not limited to the holding means by the vacuum force, and various modifications such as mechanical holding means, electrical holding means such as electrostatic force, magnetic force and the like are possible.

In the above description, the case where the invention made by the present inventor is mainly applied to the semiconductor wafer manufacturing apparatus, which is the field of use thereof, has been described, but the present invention is not limited to this, and other plate-shaped objects may be used. LCD substrate manufacturing industry,
It is widely applicable to devices in the magnetic disk manufacturing industry as well as in the multilayer wiring board manufacturing industry.

[0078]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.
It is as follows.

(1). By holding a plate-like object through a holding member made of a single crystal sapphire material, the single crystal sapphire has properties such as chemical stability, acid resistance, alkali resistance, and plasma resistance. It is possible to handle or hold the plate-like material in a clean and highly pure state by utilizing.

(2) According to the above (1), since the chemical characteristics of the single crystal sapphire material enables cleaning treatment with an acidic chemical solution, alkaline chemical solution, cleaning with a plasma treatment, and a combination thereof, a holding member. The foreign matter attached to the contact surface of can be completely removed. In particular, when the surface roughness effect is used together, the efficiency of removing foreign matter can be increased, so that cleaner handling or holding can be achieved.

(3) By holding the plate-like object on the member made of the single crystal sapphire material through the holding member on which the epitaxial silicon film has been grown, static electricity is generated by the electric conductivity of the epitaxial silicon film. Therefore, when handling or holding the plate-like object, it is possible to prevent the accumulation of foreign matter due to the adhesion of micro dust due to static electricity generated in the holding member.

(4). The shape of the contact surface of the holding member with the plate is
By making the point contact surface shape, the line contact surface shape, or a combination thereof, the contact area to the plate-shaped object can be reduced. It is possible to reduce.

(5). The contact surface of the holding member with the plate-shaped member is 0.5
By processing the flatness of less than μm and the surface roughness of Ra value of less than 0.1 μm, unevenness of the contact surface can be reduced to prevent the accumulation of foreign matter, so that the plate-like object can be handled or held. At this time, it is possible to reduce the amount of foreign matter that is transferred and adhered from the holding member to the plate-shaped material.

(6) From the above (5), the flatness of the plate-shaped article is set to 0.
Since the attitude can be controlled to 5 μm or less, it is possible to prevent processing defects caused by flatness.

(7) When the holding means is used to handle or process a plate-like object, for example, a reduction projection exposure apparatus for semiconductor wafers, the flatness of the semiconductor wafer adsorbed by the wafer holder of the exposure stage is 0.5 μm. Since the attitude can be controlled as described below, it is possible to prevent the occurrence of the resolution defect of the pattern transfer due to the flatness defect. In particular, by using the surface roughness effect together, the effect of preventing the defect in flatness of the semiconductor wafer due to the foreign matter can be further enhanced.

(8) When applied to a semiconductor wafer photoresist processing apparatus, a holding member for a wafer supporting protrusion having a micro contact surface shape and a micro height is applied on a heater block of the heat processing apparatus. As a result, the heating efficiency of the baking process is improved, and moreover, the clean heating process in which the number of foreign matter adhered from the heater surface is small can be performed.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a main part of a photoresist baking processing apparatus that is Embodiment 1 of a plate-shaped object holding means and an apparatus using the same according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a single crystal sapphire wafer holder of a reduction projection exposure apparatus which is Embodiment 2 of a plate-like object holding means of the present invention and an apparatus using the same.

FIG. 3 is a plan view showing a single crystal sapphire wafer holder of the reduction projection exposure apparatus in the second embodiment.

FIG. 4 is a front view showing a single crystal sapphire wafer holder of a reduction projection exposure apparatus according to a second embodiment.

FIG. 5 is a schematic cross-sectional view showing a main part of a spin chuck made of single crystal sapphire of a photoresist coating treatment apparatus which is Embodiment 3 of a plate-shaped article holding means of the present invention and an apparatus using the same.

[Explanation of symbols]

 1, 1a, 1b Semiconductor wafer (plate-shaped object) 2 Single crystal sapphire pin plate (holding member) 3 Heater block 4, 4a, 4b Photoresist film 5 Wafer supporting protrusion 6 Vacuum suction hole 7 Single crystal sapphire wafer holder (holding) Member) 8 exposure stage 9 exposure stage drive unit 10 UV light 11 reticle support 12 reticle 13 reduction projection lens 14 wafer transfer pin drive unit 15 wafer transfer pin 16 wafer vacuum suction port 17 outer peripheral ring 18 wafer transfer pin escape Hole 19 Wafer delivery pin relief hole ring 20 Wafer supporting protrusion 21 Wafer suction surface 22 Dropping nozzle 23 Photoresist liquid 24 Single crystal sapphire spin chuck (holding member) 25 Wafer suction surface 26 Electrically conductive silicon film

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location // H01L 21/22 M 9278-4M

Claims (5)

[Claims] 1. A plate-shaped object holding means for holding a plate-shaped object through a holding member made of a single crystal sapphire material. 2. A plate-shaped article holding means for holding a plate-shaped article on a member made of a single crystal sapphire material via a holding member on which an epitaxial silicon film is grown. 3. The plate according to claim 1, wherein a shape of a contact surface of the holding member with the plate-shaped object is a point contact surface shape, a line contact surface shape, or a combination thereof. Object holding means. 4. The contact surface of the holding member with the plate-like material is processed to have a flatness of 0.5 μm or less and a surface roughness of Ra value of 0.1 μm or less. The plate-like object holding means according to item 2. 5. An apparatus for handling or treating the plate-like object by using the plate-like object holding means according to claim 1, 2, 3, or 4.